I've just put together another in the series of beginner tutorials for OpenGLContext. This one covers the use of ARB shadow and ARB depth texture to simulate shadows.  It's based off a C tutorial and I used Ian's shader library to figure out what was going wrong with my texture matrix calculation. Turns out I forgot a transpose (duh!).

There's a few minor additions to OpenGLContext used in the tutorial, so you'll want the latest version to follow along.